Optically powered media converter

ABSTRACT

An optically powered media conversion device for performing optical to electrical conversion is disclosed. The conversion device includes at least one optical coupler for receiving at least one optical signal comprising at least one wavelength, wherein the at least one optical coupler extracts energy from the at least one optical signal, and at least one detector for extracting data from the at least one optical signal and converting the optical signal to an electrical signal using a photovoltaic process. The conversion device further includes a transmitter for converting an electrical signal to an optical signal and transmitting the optical signal to a first device.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority from U.S. Provisional PatentApplication No. 61/778,109, filed on Mar. 12, 2013, the disclosure ofwhich is hereby incorporated by reference in its entirety.

TECHNICAL FIELD

The present disclosure relates generally to management of optical signaldistribution. In particular, the present application relates to anoptically powered media converter.

BACKGROUND

Applications using fiber optics require the use of external mediaconverters to convert optical signals to electrical signals and toconvert electrical signals to optical signals. These media convertersrequire power to perform this conversion, and often receive power fromexternal devices such as a computer, keyboard, USB port, or an AC-DCpower supply that is plugged into a wall outlet. However, using an AC-DCpower supply can create problems by introducing electromagneticinterference to the optical signal. Additionally, media conversiondevices may be placed in locations far from these external powersources, thereby making it difficult or impractical to route power tosuch locations.

SUMMARY

In general terms, this disclosure is directed to optically powered mediaconverters. In one possible configuration and by non-limiting example,optically powered media converters are powered by extracting energy froman optical signal and an electrical signal.

One aspect of the present disclosure relates to a method of providingpower to a remote optical conversion device the method comprisingreceiving an optical signal at an optical interface of an electrical tooptical interface device, wherein the optical signal is delivered to theoptical interface via a fiber optical cable and includes at least onewavelength. The method further comprises extracting energy from theoptical signal and developing electrical current from the energy using aphotodetector, wherein the electrical current is developed through aphotovoltaic process. The method further comprises extractinginformation from the optical signal and transmitting information via anelectrical interface of the electrical to optical interface device.

Another aspect of the present disclosure relates to a system forproviding power to a remote conversion device, wherein the systemcomprises a first and a second device, wherein the first device includesan optical source and wherein the second device includes electricaldata. The system further comprises a media conversion device and atleast one optical fiber cable having a first end and a second end,wherein the first end is connected to the first device and the secondend is connected to the media conversion device. Additionally, thesystem comprises at least one electrical conductor cable having a firstend and a second end, wherein the first end is connected to the seconddevice and the second end is connected to the media conversion device.

Another aspect of the present disclosure relates to an optically poweredmedia conversion device for performing optical to electrical conversion,wherein the optically powered media conversion device comprises at leastone optical coupler for receiving at least one optical signal comprisingat least one wavelength, wherein the at least one optical couplerextracts energy from the at least one optical signal. The opticallypowered media conversion device further comprises at least one detectorfor extracting data from the at least one optical signal and convertingthe optical signal to an electrical signal using a photovoltaic process.Additionally, the optically powered media conversion device comprises atransmitter for converting an electrical signal to an optical signal andtransmitting the optical signal to a first device.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic block diagram of a system using an opticallypowered media converter and sensor in accordance with the presentdisclosure.

FIG. 2 is an embodiment of an optically powered media converter shown inFIG. 1.

FIG. 3 is an alternative embodiment of an optically powered mediaconverter shown in FIG. 1.

FIG. 4 is an alternative embodiment of an optically powered mediaconverter shown in FIG. 1.

FIG. 5 is an alternative embodiment of an optically powered mediaconverter, as shown in FIG. 1, with an embedded charge pump.

FIG. 6 is an embodiment of an optically powered media converter, asshown in FIG. 1, with an embedded charge pump, microcontroller, and atemperature sensor.

DETAILED DESCRIPTION

Various embodiments will be described in detail with reference to thedrawings, wherein like reference numerals represent like parts andassemblies throughout the several views. Reference to variousembodiments does not limit the scope of the claims attached hereto.Additionally, any examples set forth in this specification are notintended to be limiting and merely set forth some of the many possibleembodiments for the appended claims.

The present disclosure relates to an optically powered media converterwherein the media converter is a standalone device located externally tothe communicating devices. The present disclosure describes severalembodiments for providing optical power to the remotely located mediaconverter. In each embodiment of the present disclosure, the externallylocated media converter extracts optical energy from an inbound opticalsignal, which eliminates the need for an independent electrical powersource. In some examples described herein, a media converter can includea device with a receiver used to detect and convert optical signals tosignals of a different format (e.g., electrical signals) and optionallya transmitter used to convert signals of that different format tooptical signals.

In some embodiments, the externally located media converter requireslittle power because it does not include an optical source such as afiber optic grade light emitting diode (LED), a vertical cavitysemiconductor laser (VCSEL), a Fabry-Pérot laser, or a distributedfeedback laser. In such an embodiment, the media converter modulates apreviously received optical signal with an electrical signal includingdata desired for optical transmission. In other embodiments, theexternally located media converter includes an optical source such aslow lasing threshold current VCSEL that is powered by a charge pumpwithin the media converter. In such an embodiment, the media convertermay use anywhere between 1 to 5 mW of power.

Referring now to FIG. 1, a schematic block diagram of a system using anoptically powered media converter and sensor in accordance with thepresent disclosure is shown. In this example, the system 100 includes amedia converter 102, a first device 104, a second device 106, at leastone optical fiber 108, and at least one electrical conductor 110. Inthis example, the first device contains an internal AC-DC power supply(not shown) that is powered by an external power supply 112 using apower cable 114. The first device also includes an optical transmittercapable of generating an optical signal. Examples of opticaltransmitters useable in the first device include LEDs, Fabry-Pérotlasers, distributed feedback lasers, and VCSELs. In this embodiment, thefirst device 104 transmits the generated optical signal includinginformation and sufficient optical power over the optical fiber 108,wherein the optical signal including information is converted to anelectrical signal and optical energy is extracted by the externallylocated media converter 102. The media converter 102 then transmits theelectrical signal over an electrical conductor 110 to the second device106. Types of electrical conductors that can be used are copper cable orunshielded twisted pair. Alternatively, other types of conductive cableis used. Example embodiments of the media converter 102 are described inmore detail with reference to FIGS. 2-6.

Referring now to FIG. 2, an example embodiment of an optically poweredmedia converter 200 is shown. In various embodiments, the opticallypowered media converter 200 can be used in an optical-electricalcommunication arrangement, such as in the system 100 of FIG. 1 (e.g., asan optically powered media converter 102). The media converter 102includes first and second optical couplers 202 and 204, respectively, aphotodetector 206, and a transmitter 208. In this embodiment, the firstdevice 104 generates an optical signal with a single wavelength and withsufficient power to drive the receive function of the media converter102. The first coupler 202 within the media converter 102 extractsenergy from the optical signal and delivers the energy to drive thephotodetector 206. Using the power from the optical signal, thephotodetector 206 extracts data from the optical signal and converts theoptical signal into an electrical signal using a photovoltaic process.In some embodiments, an LED is used as a photodetector. Thephotodetector then transmits the electrical signal to the second device106, located externally to the media converter 200, over the electricalconductor 110.

The transmitter 208 part of the media converter 102 accepts electricalsignals from the second device 106 through the electrical conductor 112and extracts sufficient energy from the electrical conductor 112 todrive a switch and a modulator that is used to modulate the residualoptical signal with the electrical signal. Protocols such as Ethernetdrive the electrical conductor 112 with sufficient energy to drive aswitch and a modulator. In some embodiments, a microelectromechanicalsystems (MEMS) switch is used. In some embodiments, a cavity or aninterferometer is used as a modulator. The modulated optical signal isthen coupled onto the optical fiber 108 using the second coupler 204 andtransmitted back to the first device 104. Because the optical fiber 108transmits or receives one optical signal at a time, this firstembodiment of the present disclosure operates as a half-duplex system,or utilizes a polarization scheme to enable duplex operation.

Referring now to FIG. 3, an example of an optically powered mediaconverter 300 is shown. In various embodiments, the optically poweredmedia converter 300 can be used in an optical-electrical communicationarrangement, such as in the system 100 of FIG. 1 (e.g., as an opticallypowered media converter 102). The media converter 300 includes first andsecond optical couplers 308 and 310, respectively, a photodetector 312,and a transmitter 314. In this embodiment, the first device 302generates a first and a second optical signal at different wavelengthsthat are combined using a wave division multiplexer 304 and transmittedover the optical fiber 306. The first coupler 308 within the mediaconverter 300 extracts energy from the second optical signal anddelivers the energy to drive the photodetector 312. Using the generatedpower, the photodetector 312 extracts data from the second opticalsignal and converts the second optical signal into an electrical signalusing a photovoltaic process. The photodetector 312 then transmits theelectrical signal to the second device 106, located externally to themedia converter 300, over the electrical conductor 110.

The transmitter 314 part of the media converter 300 accepts electricalsignals from the second device 106 through the electrical conductor 112and extracts sufficient energy from the electrical conductor 112 todrive a switch and a modulator that is used to modulate the firstoptical signal with the electrical signal. Protocols such as Ethernetdrive the electrical conductor 112 with sufficient energy to drive aswitch and a modulator. In some embodiments, a MEMS switch is used. Insome embodiments, a cavity or an interferometer is used as a modulator.The first optical signal is modulated with the electrical signal and isthen coupled onto the optical fiber 306 using the second coupler 310 andtransmitted back to the first device 302. Because the optical fiber 306can simultaneously transmit and receive two optical signals, thisembodiment of the present disclosure operates as a full-duplex system.

Referring now to FIG. 4, an example of an optically powered mediaconverter 400 is shown. In various embodiments, the optically poweredmedia converter 400 can be used in an optical-electrical communicationarrangement, such as in the system 100 of FIG. 1 (e.g., as an opticallypowered media converter 102). The media converter 400 includes first andsecond optical couplers 408 and 410, respectively, a photodetector 412,a transmitter 414, and a power converter 416. In this embodiment, thefirst device 402 generates a first and a second optical signal atdifferent wavelengths that are combined using a wave divisionmultiplexer 404 and transmitted over the optical fiber 406. The firstcoupler 408 within the media converter 400 extracts part of the energyfrom the second wavelength and delivers the energy to a power converter416 that uses the energy to develop electrical current using aphotovoltaic process. This electrical power is used by the entiresystem.

Additionally, the first coupler 408 extracts the energy from the firstwavelength and delivers it to power the photodetector 412. Thephotodetector 412 then extracts data from the first wavelength andconverts the optical signal into an electrical signal using aphotovoltaic process. The photodetector 412 then transmits theelectrical signal to the second device 106, located externally to themedia converter 400, over the electrical conductor 110.

The transmitter 414 part of the media converter 400 accepts electricalsignals from the second device 106 through the electrical conductor 112and power generated by the power converter 416 to drive a switch and amodulator. In some embodiments, a MEMS switch is used. In someembodiments, a cavity or an interferometer is used as a modulator. Thesecond optical signal is modulated with the electrical signal and isthen coupled onto the optical fiber 406 using the second coupler 410 andtransmitted back to the first device 402. Because the optical fiber 406can simultaneously transmit and receive two optical signals, thisembodiment of the present disclosure operates as a full-duplex system.

Referring now to FIG. 5, an example embodiment of an optically poweredmedia converter 500 using discrete transmit and receive optical fibers504 and 506, respectively, is shown. In various embodiments, theoptically powered media converter 500 can be used in anoptical-electrical communication arrangement, such as in the system 100of FIG. 1 (e.g., as an optically powered media converter 102). The mediaconverter 500 includes a splitter 508, a photovoltaic cell 510, a chargepump 512, a storage device 514, a PIN detector 516, a first driver 518,a second driver 520, and an optical transmitter 522. In this embodiment,the first device 502 transmits an optical signal containing power anddata over the transmit optical fiber 504. The optical signal terminatesat a splitter 508 in the media converter 500 wherein the splitter 508divides part of the energy to a PIN detector 516 for data extraction andsends the remaining part to a photovoltaic cell 510 for powerextraction. In some embodiments, the splitter 508 evenly divides thesignal power between to the PIN detector 516 and the photovoltaic cell510. In other embodiments, the splitter 508 divides the signal in otherratios wherein the higher side is used for power.

The PIN detector 516 is used to extract data from the first wavelength.The PIN detector 516 outputs the data as an electrical signal that istransmitted to the second device 106, located externally to the mediaconverter 500, over the electrical conductor 110 using the first driver518. In other embodiments, the electrical signal is transmitted to thesecond device 106 using a PHY device such as an Ethernet PHY chip.

As described above, the photovoltaic cell 510 receives a divided signalfrom the splitter 508 and extracts power therefrom. The photovoltaiccell 610 powers a charge pump 512 that generates a higher voltage thanthe incoming supply voltage using one or more capacitors. The chargepump 512 regulates the current supplied to the storage device 514thereby enabling the storage device 514 to store energy that is thenused by the media converter 500. In some embodiments, a super capacitoris used as the storage device 514. In other embodiments a battery isused. In some embodiments, the storage device 514 is factory pre-chargedand in other embodiments, the storage device is not pre-charged.

The media converter 500 also sends an optical signal carrying data froman electrical signal generated by the second device 106 to the firstdevice 104 over the receive optical fiber 506. In this embodiment, anoptical signal is generated by an optical transmitter 522. Examples ofan optical transmitter used by the media converter 500 are an LED, aFabry-Pérot laser, a distributed feedback laser, or a VCSEL. In thisembodiment, the optical transmitter 522 is driven by a driver 520 withthe electrical signal transmitted from the second device 106 as theinput signal. The generated optical signal including information fromthe electrical signal is then transmitted to the first device 502 overthe receive optical fiber 506. Because the transmit and receive opticalfibers 504 and 506, respectively, can simultaneously transmit andreceive two optical signals, this embodiment of the present disclosureoperates as a full-duplex communication system.

Referring now to FIG. 6, an example embodiment of an optically poweredmedia converter 600 using discrete transmit and receive optical fibers604 and 606, respectively, is shown. In various embodiments, theoptically powered media converter 600 can be used in anoptical-electrical communication arrangement, such as in the system 100of FIG. 1 (e.g., as an optically powered media converter 102). The mediaconverter 600 includes a splitter 608, a photovoltaic cell 610, a chargepump 612, a storage device 614, a PIN detector 616, a microcontroller618, a temperature sensor 620, and an optical transmitter 622. In thisembodiment, the first device 602 transmits an optical signal containingpower and data over the transmit optical fiber 604. The optical signalterminates at a splitter 608 in the media converter 600 wherein thesplitter 608 divides part of the energy to a PIN detector 616 for dataextraction and sends the remaining part to a photovoltaic cell 610 forpower extraction. In some embodiments, the splitter 608 evenly dividesthe signal power between to the PIN detector 616 and the photovoltaiccell 610. In other embodiments, the splitter 608 divides the signal inother ratios wherein the higher side is used for power.

The PIN detector 616 and built-in amplifiers in the microcontroller 618extract data from the first wavelength. The microcontroller 618 outputsthe data as an electrical signal on a general purpose input/output pinand transmits the electrical signal to the second device 106, locatedexternally to the media converter 600, over the electrical conductor110.

As described above, the photovoltaic cell 510 receives a divided opticalsignal from the splitter 508 and extracts power therefrom. Thephotovoltaic cell 610 powers a charge pump 612 that generates a highervoltage than the incoming supply voltage using one or more capacitors.The charge pump 612 regulates the current supplied to the storage device614 thereby enabling the storage device 614 to store energy that is thenused by the media converter 600. In some embodiments, a super capacitoris used as the storage device 614. In other embodiments a battery isused. In some embodiments, the storage device 614 is factory pre-chargedand in other embodiments, the storage device is not pre-charged.

In this embodiment, the media converter 600 also sends an optical signalcarrying data from an electrical signal generated by the second device106 and temperature data generated by the temperature sensor 620 to thefirst device 602. In this embodiment, the microcontroller 618 receivesdata from the first device 106 and the embedded temperature sensor 620.Alternatively, the temperature sensor 620 is located externally to themedia converter 600 in other embodiments. An optical transmitter 622that is driven by the microcontroller 618 generates an optical signal.Examples of an optical transmitter 622 used by the media converter 600are a VCSEL, an LED, a Fabry-Pérot laser, or a distributed feedbacklaser. In this embodiment, a VCSEL is used as the optical transmitter622 due to its low lasing threshold current, allowing themicrocontroller 618 to drive the VCSEL using a general purposeinput/output pin. The generated optical signal is then transmitted tothe first device 602 over the receive optical fiber 606. Because thetransmit and receive optical fibers 604 and 606, respectively, cansimultaneously transmit and receive two optical signals, this embodimentof the present disclosure operates as a full-duplex communicationsystem.

The various embodiments described above are provided by way ofillustration only and should not be construed to limit the claimsattached hereto. Those skilled in the art will readily recognize variousmodifications and changes that may be made without following the exampleembodiments and applications illustrated and described herein, andwithout departing from the true spirit and scope of the followingclaims.

What is claimed is:
 1. A method of providing power to an opticalconversion device, the method comprising: receiving from a firstexternal device an optical signal at an optical interface of anelectrical to optical conversion device, wherein the optical signal isdelivered to the optical interface via a fiber optical cable andincluding at least one wavelength; splitting the optical signal into afirst optical signal and a second optical signal; extracting energy fromthe first optical signal; developing electrical current from the energyusing a detector, wherein the electrical current is developed through aphotovoltaic process; storing electrical energy at a storage device viaa charge pump receiving the electrical current; extracting data from thesecond optical signal; converting the data to an electrical signal; andtransmitting the electrical signal to an external device via anelectrical interface of the electrical to optical interface device. 2.The method of claim 1, wherein the detector comprises a photodiode. 3.The method of claim 1, wherein extracting energy from the first opticalsignal further comprises: extracting energy from a first wavelength ofthe optical signal.
 4. The method of claim 1, further comprising:delivering the energy to the electrical to optical interface device. 5.The method of claim 1, further comprising: receiving an electricalsignal from an electrical interface, wherein the electrical signalincludes data and power; modulating a residual optical signal with theelectrical signal to generate a modulated signal; and transmitting themodulated signal via the optical interface.
 6. The method of claim 5,wherein the electrical interface is electrically connected to anunshielded twisted pair electrical interface.
 7. A system for providingpower to a remote conversion device, the system comprising: a first anda second device, wherein the first device includes an optical source andwherein the second device includes electrical data; a media conversiondevice comprising: at least one optical coupler that extracts part ofthe energy from the at least one wavelength; a detector, wherein thedetector extracts the optical data from the at least one wavelength andwherein the detector further converts the optical data to electricaldata; a splitter for dividing the at least one wavelength into a firstsignal power and a second signal power; a charge pump; a storage deviceelectrically connected to the charge pump; a photovoltaic cell forextracting energy from the second signal power and delivering the energyto the charge pump; a transmitter, wherein the transmitter accepts theelectrical data from the second device and further converts theelectrical data to a second optical signal and further transmits thesecond optical signal to the first device; at least one optical fibercable having a first end and a second end, wherein the first end isconnected to the first device and the second end is connected to themedia conversion device; and at least one electrical conductor cablehaving a first end and a second end, wherein the first end is connectedto the second device and the second end is connected to the mediaconversion device.
 8. The system of claim 7, wherein the optical sourcegenerates an optical signal with at least one wavelength and furtherwherein the optical signal includes optical data and energy.
 9. Thesystem of claim 7 wherein the media conversion device further comprisesa power converter, wherein the power converter uses the energy extractedfrom the at least one optical coupler to develop electrical current usedby the media converter.
 10. The system of claim 7, wherein the mediaconversion device further comprises: a microcontroller; a PIN detector,wherein the pin detector extracts data from the second wavelength andtransmits the data to the microcontroller; and a temperature sensorelectrically connected to the microcontroller, wherein the temperaturesensor sends temperature data to the microcontroller.
 11. An opticallypowered media conversion device for performing optical to electricalconversion, wherein the optically powered media conversion devicecomprises: at least one optical coupler for receiving at least oneoptical signal comprising at least one wavelength, wherein the at leastone optical coupler extracts energy from the at least one opticalsignal; at least one detector for extracting data from the at least oneoptical signal and converting the optical signal to an electrical signalusing a photovoltaic process; a splitter for dividing the at least onewavelength into a first signal power and a second signal power; a chargepump; a storage device electrically connected to the charge pump; aphotovoltaic cell for extracting energy from the second signal power anddelivering the energy to the charge pump and storage device; and atransmitter for converting an electrical signal to an optical signal andtransmitting the optical signal to a first device.
 12. The device ofclaim 11, wherein the optically powered media conversion device furthercomprises: a PIN diode for extracting data from the first signal power;wherein the charge pump is electrically connected to the PIN diode andcharges the storage device.
 13. The device of claim 12, wherein thestorage device further comprises a battery or a super capacitor.
 14. Thedevice of claim 12, wherein the storage device further comprises a supercapacitor.
 15. The device of claim 12, wherein the splitter divides theat least one wavelength into a first signal power and a second signalpower evenly.